Automatic straightening and stripping device for punching and shearing machines



Aug. 26 1924.

V R. B. HANCOGK ING DEVICE FOR PUNGHING AND SHEARING MACHINES AUTOMATIC STRAIGHTENING AND STRIPP Filed latch 10, 1922 3 Shuts-Shut 1 Aug. 26, 1924. 1,506,424

- R. B. HANCOCK AUTOMATIC STRAIGHTENING AND STRIPPING- DEVICE FOR PUNCHING AND SHEARING MACHINES Filed March 10, 1922 s Shuts-Shoat 2 'uvfi W d/ y R. B. HANCOCK AUTOMATIC STRAIGHTENING AND STRIP? ING DEVICE FOR PUNCHING AND SHEARING MACHINES Filed March 10 1922 3 Shun-Shut 5 Jill I Fifi! Patented Aug. 26, 192 5.

FICE.

RANDOLPH B. HANCOCK, OE GAB-3f, INDIANA.

AUTOMATIC STBAIGHTENING AND STBIPPING DEVICE FOR PUNCHING AND SHEAR/ENG MACHINES.

Application filed March 10, 1922.

T 0 all whom it may concern:

Be it known that I, RANDOLPH B. HAN- coon, a citizen of the United States, residing at Gary in the county of Lake and State of Indiana, have invented certain new and useful Improvements in Automatic Straightening and Stripping Devices for Punching and Shearing Machines, of which the following is a specification.

My invention relates to combined automatic straightening and stripping devices for use in punching and shearing metal and has particular reference to a straightening and stripping device for use on punch presses, shearing machines and the like.

The primary object of my invention is the provision of a straightening and stripping mechanism actuated by a high pressure fluid in synchronism with the operation of the machine and which is entirely auto matic in its operation and which holds and straightensthe work-piece during the operation of the machine and which will also free the punching dies or shear from the material upon which the machine is operating after the punching or shearing operation is complete and will also straighten the work-piece upon the die simultaneous with the punching and stripping operation.

In the production of plates of various kinds, it has been the practice heretofore to run the plates after they have been punched or sheared through a press in order to straighten them and put them in condition for use, as they are bent and distorted by the shearing or punching operation and the punches are liable also to pull slugs or burrs back through the dies causing them to fall under the plate to be punched next and spoiling it. In addition to this feature. in practice it has been proven that because of the material. upon which the press is operated sticking to the dies or to the shear a great deal of time is lost because when the material sticks to the dies it has to be pried loose and many times the operation of the machine sto ped until the material is removed. resultino in dama ing or destroying the work-piece freouentlv' and a loss of a number of strokes of the machine before it can he started in operation again. A so in the o eration of machines of this kind many times the operator will attem t to free 'the working; mechanism on the workpiece without stopping the Serial No. 542,679.

machine resulting in injury to himself, the loss of his fingers or hand, and thus seriously interfering with the operation of these machines.

By the use of my improved device the stiaight-ening process and the stripping operation performed automatically and results in each stroke of the machine performing an operation upon the work-piece and also the complete elimination of one process so that there is no loss in time in the operation of the machine, and also the work turned out from the machine is of uniform quality and the capacity of the machine is thereby increased.

These and other objects of my invention will be more readily and better understood by those skilled in the art by reference to the accompanying drawings. and in which- Figure 1 is a front elevational view of a machine equipped with my improved stripping: mechanism;

Fig. 2 is a side view partially in section and partially in elevation of my improved device;

Fig. 3 is a sectional view on line 3-3 of Fig. 2:

Fig. 4 is an elevational view showing the air valve operating mechanism; and

Fig. 5 is a sectional view on line 5-5 of Fig. 4:.

Referring now specifically to the drawino s. a-machine frame 10 is shown having a horizontal driving shaft 11 mounted thereon to which is secured belt wheel through which power is communicated to the machine in the usual manner. A shield 12 is provided which covers the belt wheel and operating mechanism. Secured to the shaft 11 in the usual manner is a punching head 13 having the usual punching; dies 14. 14'. secured thereto in any approved manner. h founted upon the frame of the machine is a punching table 15 to which a die block 16 is secured upon which a work-piece 17 rests during the punching operation. The punchinn head 13 also has secured thereto a shear 18 by means of a bolt 19 in the usual 'manner. Secured to the frame 10 of the machine by means of bolts 19 is a pair of brackets 20, 21 and to which is secured a plate 22 formed integral with a shaft portion. 23 which is mounted in the brackets 20 and 21 respectively, so that the plate 22 is held in position over die block 16 of the punching machine, the plate 22 performing the double function of holding the work-piece and stripping it from the punching dies 14, 14, and also straightening the work-piece upon the die block 16 during the punching opera tion. The plate 22 has perforations 24, 25 therein through which the punching dies 14, 14 pass during the operation of the machine. Secured to the frame 10 of the machine is a bracket 26 which is held in position by means of bolts 26, and has secured thereto by means of bolts 26", 26 a cylinder 27 having a piston 28 mounted therein, with a piston head 28 secured thereto, the cylinder 27 having an end cap 29 secured thereto in any approved manner to which a gland 30 is secured by means of bolts 31, 31. Ports 27" and 27 are provided in the cylinder 27 for the admission of a high pressure fluid to the cylinder 27 as hereinafter described. Secured to the upper end of the piston 28 is a threaded block 32 having a pin 33 mounted therein, the upper end of the piston 28 being threaded and a locking nut 34 in threaded engagement therewith holding the block 32 securely in position on the end of the piston. Secured at its rearward end to the piston 28 is a lever 35 bifurcated at its rear end and having a bolt 36 extending therethrough which holds the said lever 35 in position upon the pin 33. The pin 33 extends between the forked ends of the lever 35 so that as the piston 28 moves the lever 35 will also be moved. The forward end of the lever 35 "is secured to the shaft portion 23 of the plate 22 by means of a bolt 37 so that as the rear end of the lever 35 is moved by the piston in the manner as hereinafter described, the shaft portion 23 of the stripper blade will be rotated thus bringing'the blade 22 down upon the work-piece 17 and holding it during the punching operation.

Mlounted upon the frame 10 at the rear end of the machine by means of bolts 39, 39,

is a plate 38 to which a valve chest 40 is secured by means of bolts 41, 41, the said valve chest comprising a block 42 and a cover 43 which is held in position by means of the bolts 41, 41 which extend through the block 42 and under which a valve chamber 42 is formed. Extending transversely through the block 42 is a series of passages 44, 45, 46 and 47 with which pipes 48, 49, 50, and 51 communicate respectively, the said pipes being in threaded engagement with the block 42. Each of the passages 44, 45, 46 and 47 are closed at their ends opposite the pipes 48, 49, and 51 by means of plugs The pipe 48 leads to any suitable source of compressed air or other high pressure fluid and through which a constant supply of compressed air is supplied to the valve chamber 42 The pipe49 leads to the cylinder 27 and isconnected thereto at the opening 27 in aid cylinder 27 for the admission, and exhaust of compressed air to and from said cylinder below the piston head 28*. The pipe 51 also leads to the cylinder 27 and is connected thereto at the opening 27 in the upper side of the cylinder for the admission and exhaust of compressed air to and from said cylinder above the piston head 28*. The pipe 50 is an exhaust pipe leading to the atmosphere and is alternately connected with the pipes 49 and 51 through the passages in the block 42 and the valve 57 for the exhaust of the compressed air from the cylinder 27. The passage 44 extending through the block 42 has an intake port 53 extending from said passage 44 to the valve chamber 42 of the valve chest. An exhaust port 55 leads from the exhaust passage 46 to the valve chamber 42 and similar ports 54 and 56 lead from the passages 45 and 47 respectively to the valve chamber 42 and through which compressed air is admitted to and exhaustedfrom the cylinder 27 as hereinafter described; Mounted in the valve chamber 42 in sliding engagement with the block 42 is a slide valve 57 to which a piston 58 is connected, the piston 58 at its forward end being enlarged and operating inside of and in sliding engagement with the sleeve portion 59 of the cover plate 43, thereby serving as a guide and as a packing member for the valve chamber 42 The piston 58- is bifurcated at its forward end and has a roller 60 mounted thereon by means of a bolt 61. Secured to the driving shaft 11 by means of bolts 62, 62 is a cam member 63, the said cam member having slots 64, 65, extending therethrough and through which the bolts 62, 62 extend so that the said cam member 63 can be adjusted to different positions upon the rear end of the shaft 11. The valve 57 has continuously extending port 66 therethrough, the said port 66 being arcuate in shape and terminating just short of the ends of the valve 57 on the side adjacent the block 42 so that the port 66 at each of its ends registers at pre determined times with the ports 54 and 56 respectively in the block 67 and 68 in spaced relation with each other are provided through the side of thevalve 57 between the ends of the port 66 which communicate with the port 66 and which are adapted to register alternately with the exhaust port 55 through the block 42 which leads to the exhaust passage 46; r

In operation, the plate the lever 35 connected to the piston 28 in the cylinder 27 and into which compressed air is admitted and exhausted by the movement of the valve 57 which is controlled by the rotation of the driving shaft 11. The pipe 48, leading to the valve chest 40 isconnected to any suitable source of compressed air or other high pressure fluid so that a supply of compressed air is furnished to the valve chamber 42' is actuated by at all times, the compressed air 1 42. A pair of ports portion ofthe said eccentric, the valve 57 is forced backwards and brings the one end of port 66 over the port 54 and'the port 68 into register with the port '55 at which position of the valve 57 the passagesa and %6 are connected, thence bringing the ports '67 and 68 into register with the slit which communicates with the passage 46. The-pipe e9 leads to the lower end of the cylinder 27 and the pipe 51' to the upperend of the cylinder 27, and the pipe 50 which communicates with the passage et6 in the block 42 1eading to the atmosphere and providing means for exhaust in the air from the cylinder 27: As the cam member 63 is rotated through the action of the driving shaft 11 the slide valve 57 will be pushed forwardly of the valve chamber 42 in the position shown in Fig. 5 of the drawing, so that compressed air is admitted through the slot 54, passage 4:5 and pipe L9 to the lower end of the cylinder 27, thus forcing the rear end of the lever 35 upward and the plate 22 downward at the same time as the punch head 13 carrying the punching dies, 14, 14, descends, so the work-piece is surely held during the punching operation and until this operation is complete, the work-piece 17 being held until the dies are withdrawn so that the work-piece 17 is not distorted by the straightened if it has been distorted in any manner prior to its reaching the punching dies. Thereupon, as the shaft 11 is rotated the roller 60 traveling around the cam surface comes to the enlarged portion of the member 63 the valve 57 is forced over the port 5% so that a communicating passage is formed through the pipe 49, passage &5 and ort 54 and a portion of the passage 66 and 68 with the exhaust passages 55 and 46, so that the air is exhausted from the bottom of the cylinder, the passage 56 in the meantime being uncovered so that a supply of compressed air enters the upper end of the cylinder 27 through the passages 56 and 47, the pipe 51 thereby forcing the piston 28 in the cylinder 27 downward and pulling the plate 22 out of contact with the work-piece 17 upon the die block 16 of the punch press.

The sequence of operation above described is continuous until the operation of the punch press is stopped, and it will be understood that the operation of the stripping plate 22 is automatically controlled and operates in synchronism with the operation of the punching head 13 of the press.

It will also be understood that while I have illustrated and described a straighten -a pivotally mounted stripping v1nder', a piston 1n said cylinder,

punching operation and is mg and stripping mechanism secured to a punch press having a shearing attaclunent, it can also be used upon a machine for shearing alone,'or forpunching alone, or upon a ma chine which is used for stamping as well as forpunching operations.

hile I have'described more or less pre cisely the details of construction, I do not wish to be understood as limiting myself thereto, as I contemplate changes in form and the proportion of parts and the substitution of equivalents as circumstances may suggest or render expedient without departing from the spirit or scope of my invention.

I claim:

1. In combination, with a punching press plate, a cyloperating connections between said stripping plate and said piston, and means whereby fluid pres sure is admitted into and exhausted from said cylinder whereby said stripping plate is operated in synchronism with the punching head of the press.

2. In combination with a punching press, a pivotally mounted stripping plate, a cylinder secured to the frame of said press, a piston in said cylinder, operative connection between said piston and said stripping plate and means whereby a fluid pressure is admitted to said cylinder above and below said piston in synchronism with the movement with the punching head of said press.

3. In combination with a punching press having a driving shaft, a pivotally mounted stripping plate, an operating cylinder secured to the frame of said press, a piston in said cylinder, operative connections between said piston and said stripping plate, a source of fluid pressure, a valve block having a plurality of ports therein, a valve slidably mounted upon said block, operative connections between said valve and the driving shaft of said punching press, the ports in said block being connected to a source of fluid pressure supply and to the said cylinder.

a. In combination with a punching press having a driving shaft and punching dies, a pivotally mounted plate, an operating cylinder secured to the frame of said press, a piston in said cylinder, a lever connecting said piston with said pivotally mounted plate, a valve-chest having a plurality of ports therein, a valve in said valve-chest, an eccentric secured to the shaft of said press whereby the said valve is operated for admission of a fluid pressure to said cylinder and exhaust therefrom in synchronism with the operation of the punching dies of the said press.

5. In combination with a punching press having a driving shaft and punching dies, a pivotally mounted plate, an operating cylinder secured to the frame of said press, a

' said piston With said piston in said cylinder, a lever connecting pivotally mounted plate, a valvechest having a plurality of ports therein, a valve in said valve-chest, an eccentric adjustably secured to the shaft of said press whereby the said valve is operated for admission of a fluid pressure to said cylinder and exhaust therefrom in synchronism With the operation of the punching dies of the said press.

6. In combination with a punching press having a driving shaft and punching dies, a pivotally mounted plate secured thereto, an operating cylinder secured to the frame of said press, a piston in said cylinder, a lever connecting said piston With said pivotally mounted plate, a valve block having a plurality of ports therein, one of said ports being connected to a source of fluid pressure, and one of the ports acting as an exhaust port, a valve slidably mounted upon said chronism with the punching valve block and adapted to control by the operation of the drive shaft of said press the admission of fluid pressure of said cylinder pivotally mounted plate, an operating cylinder secured to the frame of said press, a piston in said cylinder, a lever conected to said pivotally mounted plate at one end and adjustably secured to the piston at its opposite end, and means whereby a fluid pressure is admitted to and exhausted from-said cylinder whereby the plate is operated in synpress.

Signed at Gary, Indiana, of February, 1922.

RANDOLPH B. HANCOCK.

this 25th day dies of said 

